2 * Copyright (C) 2012, Analog Devices Inc.
3 * Author: Lars-Peter Clausen <lars@metafoo.de>
6 * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
7 * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
8 * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
9 * Copyright (C) 2006 Applied Data Systems
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/dmaengine.h>
24 #include <linux/slab.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
29 #include <sound/dmaengine_pcm.h>
31 struct dmaengine_pcm_runtime_data {
32 struct dma_chan *dma_chan;
38 static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
39 const struct snd_pcm_substream *substream)
41 return substream->runtime->private_data;
44 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
46 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
48 return prtd->dma_chan;
50 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
53 * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
54 * @substream: PCM substream
56 * @slave_config: DMA slave config
58 * This function can be used to initialize a dma_slave_config from a substream
59 * and hw_params in a dmaengine based PCM driver implementation.
61 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
62 const struct snd_pcm_hw_params *params,
63 struct dma_slave_config *slave_config)
65 enum dma_slave_buswidth buswidth;
68 bits = params_physical_width(params);
69 if (bits < 8 || bits > 64)
72 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
74 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
76 buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
78 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
80 buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
82 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
83 slave_config->direction = DMA_MEM_TO_DEV;
84 slave_config->dst_addr_width = buswidth;
86 slave_config->direction = DMA_DEV_TO_MEM;
87 slave_config->src_addr_width = buswidth;
90 slave_config->device_fc = false;
94 EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
97 * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
99 * @substream: PCM substream
100 * @dma_data: DAI DMA data
101 * @slave_config: DMA slave configuration
103 * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and
104 * slave_id fields of the DMA slave config from the same fields of the DAI DMA
105 * data struct. The src and dst fields will be initialized depending on the
106 * direction of the substream. If the substream is a playback stream the dst
107 * fields will be initialized, if it is a capture stream the src fields will be
108 * initialized. The {dst,src}_addr_width field will only be initialized if the
109 * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of
110 * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If
111 * both conditions are met the latter takes priority.
113 void snd_dmaengine_pcm_set_config_from_dai_data(
114 const struct snd_pcm_substream *substream,
115 const struct snd_dmaengine_dai_dma_data *dma_data,
116 struct dma_slave_config *slave_config)
118 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
119 slave_config->dst_addr = dma_data->addr;
120 slave_config->dst_maxburst = dma_data->maxburst;
121 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
122 slave_config->dst_addr_width =
123 DMA_SLAVE_BUSWIDTH_UNDEFINED;
124 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
125 slave_config->dst_addr_width = dma_data->addr_width;
127 slave_config->src_addr = dma_data->addr;
128 slave_config->src_maxburst = dma_data->maxburst;
129 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
130 slave_config->src_addr_width =
131 DMA_SLAVE_BUSWIDTH_UNDEFINED;
132 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
133 slave_config->src_addr_width = dma_data->addr_width;
136 slave_config->slave_id = dma_data->slave_id;
138 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
140 static void dmaengine_pcm_dma_complete(void *arg)
142 unsigned int new_pos;
143 struct snd_pcm_substream *substream = arg;
144 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
146 new_pos = prtd->pos + snd_pcm_lib_period_bytes(substream);
147 if (new_pos >= snd_pcm_lib_buffer_bytes(substream))
151 snd_pcm_period_elapsed(substream);
154 static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
156 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
157 struct dma_chan *chan = prtd->dma_chan;
158 struct dma_async_tx_descriptor *desc;
159 enum dma_transfer_direction direction;
160 unsigned long flags = DMA_CTRL_ACK;
162 direction = snd_pcm_substream_to_dma_direction(substream);
164 if (!substream->runtime->no_period_wakeup)
165 flags |= DMA_PREP_INTERRUPT;
168 desc = dmaengine_prep_dma_cyclic(chan,
169 substream->runtime->dma_addr,
170 snd_pcm_lib_buffer_bytes(substream),
171 snd_pcm_lib_period_bytes(substream), direction, flags);
176 desc->callback = dmaengine_pcm_dma_complete;
177 desc->callback_param = substream;
178 prtd->cookie = dmaengine_submit(desc);
184 * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
185 * @substream: PCM substream
186 * @cmd: Trigger command
188 * Returns 0 on success, a negative error code otherwise.
190 * This function can be used as the PCM trigger callback for dmaengine based PCM
191 * driver implementations.
193 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
195 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
196 struct snd_pcm_runtime *runtime = substream->runtime;
200 case SNDRV_PCM_TRIGGER_START:
201 ret = dmaengine_pcm_prepare_and_submit(substream);
204 dma_async_issue_pending(prtd->dma_chan);
206 case SNDRV_PCM_TRIGGER_RESUME:
207 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
208 dmaengine_resume(prtd->dma_chan);
210 case SNDRV_PCM_TRIGGER_SUSPEND:
211 if (runtime->info & SNDRV_PCM_INFO_PAUSE)
212 dmaengine_pause(prtd->dma_chan);
214 dmaengine_terminate_async(prtd->dma_chan);
216 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
217 dmaengine_pause(prtd->dma_chan);
219 case SNDRV_PCM_TRIGGER_STOP:
220 dmaengine_terminate_async(prtd->dma_chan);
228 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
231 * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
232 * @substream: PCM substream
234 * This function is deprecated and should not be used by new drivers, as its
235 * results may be unreliable.
237 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
239 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
240 return bytes_to_frames(substream->runtime, prtd->pos);
242 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
245 * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
246 * @substream: PCM substream
248 * This function can be used as the PCM pointer callback for dmaengine based PCM
249 * driver implementations.
251 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
253 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
254 struct dma_tx_state state;
255 enum dma_status status;
256 unsigned int buf_size;
257 unsigned int pos = 0;
259 status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
260 if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
261 buf_size = snd_pcm_lib_buffer_bytes(substream);
262 if (state.residue > 0 && state.residue <= buf_size)
263 pos = buf_size - state.residue;
266 return bytes_to_frames(substream->runtime, pos);
268 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
271 * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
272 * @filter_fn: Filter function used to request the DMA channel
273 * @filter_data: Data passed to the DMA filter function
275 * Returns NULL or the requested DMA channel.
277 * This function request a DMA channel for usage with dmaengine PCM.
279 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
285 dma_cap_set(DMA_SLAVE, mask);
286 dma_cap_set(DMA_CYCLIC, mask);
288 return dma_request_channel(mask, filter_fn, filter_data);
290 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
293 * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
294 * @substream: PCM substream
295 * @chan: DMA channel to use for data transfers
297 * Returns 0 on success, a negative error code otherwise.
299 * The function should usually be called from the pcm open callback. Note that
300 * this function will use private_data field of the substream's runtime. So it
301 * is not available to your pcm driver implementation.
303 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
304 struct dma_chan *chan)
306 struct dmaengine_pcm_runtime_data *prtd;
312 ret = snd_pcm_hw_constraint_integer(substream->runtime,
313 SNDRV_PCM_HW_PARAM_PERIODS);
317 prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
321 prtd->dma_chan = chan;
323 substream->runtime->private_data = prtd;
327 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
330 * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
331 * @substream: PCM substream
332 * @filter_fn: Filter function used to request the DMA channel
333 * @filter_data: Data passed to the DMA filter function
335 * Returns 0 on success, a negative error code otherwise.
337 * This function will request a DMA channel using the passed filter function and
338 * data. The function should usually be called from the pcm open callback. Note
339 * that this function will use private_data field of the substream's runtime. So
340 * it is not available to your pcm driver implementation.
342 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
343 dma_filter_fn filter_fn, void *filter_data)
345 return snd_dmaengine_pcm_open(substream,
346 snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
348 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
351 * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
352 * @substream: PCM substream
354 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
356 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
358 dmaengine_synchronize(prtd->dma_chan);
363 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
366 * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel
367 * @substream: PCM substream
369 * Releases the DMA channel associated with the PCM substream.
371 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
373 struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
375 dmaengine_synchronize(prtd->dma_chan);
376 dma_release_channel(prtd->dma_chan);
381 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
383 MODULE_LICENSE("GPL");